How to delay an ARM Cortex M0+ for n cycles, without a timer?

Question

I want to delay an ARM Cortex M0+ for n cycles, without using a timer, with the smallest possible code size. (I think this mandates use of assembly.)

A delay of 0 c

Answer 1

The shortest ARM loop that I can think of goes like:

mov r0, #COUNT
L:
subs r0, r0, #1
bnz L

Since I don't have the device in question, no idea about timing. Those are core dependent.